Details: File format summary

Details for:

Go to: Summary | Documentation

| Signatures

| Compression

| Rights

Properties

Summary
Name	Adaptive Multi-Rate Audio
Version
Other names	AMR-NB, GSM-AMR
Identifiers	MIME: audio/amr PUID: fmt/356
Family
Classification	Audio
Disclosure
Description	The Adaptive Multi-Rate (AMR or AMR-NB or GSM-AMR) audio codec is an audio compression format optimized for speech coding. AMR speech codec consists of a multi-rate narrowband speech codec that encodes narrowband (200–3400 Hz) signals at variable bit rates ranging from 4.75 to 12.2 kbit/s with toll quality speech starting at 7.4 kbit/s.
Orientation	Text
Byte order
Related file formats	Can be contained by 3GPP Audio/Video File
Technical Environment
Released
Supported until
Format Risk
Developed by	None.
Supported by	None.
Source	Digital Preservation Department / The National Archives
Source date	17 Jun 2011
Source description
Last updated	17 Jun 2011
Note